EP1760268B1 - Dispositif pour contrôler le contact dans un assemblage statorique - Google Patents

Dispositif pour contrôler le contact dans un assemblage statorique Download PDF

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Publication number
EP1760268B1
EP1760268B1 EP06254529.8A EP06254529A EP1760268B1 EP 1760268 B1 EP1760268 B1 EP 1760268B1 EP 06254529 A EP06254529 A EP 06254529A EP 1760268 B1 EP1760268 B1 EP 1760268B1
Authority
EP
European Patent Office
Prior art keywords
stator
base
adjacent
circumferentially
vane
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
EP06254529.8A
Other languages
German (de)
English (en)
Other versions
EP1760268A3 (fr
EP1760268A2 (fr
Inventor
Hani Ikram Noshi
Josef Scott Cummins
Steven E. Tomberg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Publication of EP1760268A2 publication Critical patent/EP1760268A2/fr
Publication of EP1760268A3 publication Critical patent/EP1760268A3/fr
Application granted granted Critical
Publication of EP1760268B1 publication Critical patent/EP1760268B1/fr
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D9/00—Stators
    • F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
    • F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
    • F01D9/042—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector fixing blades to stators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12—Blades
    • F01D5/14—Form or construction
    • F01D5/16—Form or construction for counteracting blade vibration
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D9/00—Stators
    • F01D9/02—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles
    • F01D9/04—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector
    • F01D9/041—Nozzles; Nozzle boxes; Stator blades; Guide conduits, e.g. individual nozzles forming ring or sector using blades

Definitions

  • This application relates generally to turbine engines and, more particularly, to methods and apparatus for controlling contact within turbine engine stator assemblies.
  • At least some known rotor assemblies include at least one row of circumferentially-spaced rotor blades. Each row of rotor blades is positioned between a pair of axially-spaced rows of circumferentially-spaced stator vanes or blades. At least some known stator vanes are fabricated with a base and an integrally-formed airfoil that extends radially outward from the base. Each base is configured to couple the stator vanes within the engine such that the stator vanes extend radially through a flow path defined within the rotor assembly.
  • the base of each stator vanes is substantially wedge-shaped or square based such that a radially outer surface of the base may have an arcuate length that is longer than a corresponding length of a radially inner surface of the base.
  • the wedge shape facilitates coupling the stator vanes circumferentially within the stator assembly.
  • the geometry of the base also makes control of contact between adjacent stator vanes, known as circumferential contact, and between each stator vanes and the casing, known as axial contact, difficult to accurately predict.
  • excitation responses generated by such stator vanes often do not match predicted experimental frequencies. Over time, the increased excitation responses may result in shortening the useful life of the stator vanes.
  • United States Patent No. 6217282 describes a vane element adapted for assembly with a plurality of further vane elements to form a ring of vanes for a low pressure gas turbine.
  • Each vane element has a vane blade with platforms at its outer and inner ends, the platform at the outer end being adapted for connection to a housing.
  • Each platform has a flange integral with the vane blade and an outer wall spaced radially from the flange and joined thereto by a radial wall having a lateral projection.
  • a recess is formed between the flange and the outer wall, the recess having a shape corresponding to that of the projection so that a plurality of the vane elements can be assembled to form the vane ring by engaging the projection of one vane element in the recess of an adjacent vane element.
  • the projections are form-fit in the recesses so that the platforms of the vane elements are flush with one another.
  • the present invention resides in a rotor assembly comprising, a rotor shaft and a plurality of stator vanes circumferentially-spaced around said rotor shaft, each said stator vane comprising a base and an integrally-formed airfoil extending radially outward from said base, each base comprising a radially outer surface and a radially inner surface and a pair of circumferentially-spaced sides coupled together by an upstream side and a downstream side, wherein a recessed portion is defined within at least one of said circumferentially-spaced sides extending from radially outer surface towards radially inner surface, such that a hinge is created adjacent the radially inner surface, wherein a gap is defined between circumferentially adjacent stator vanes and contact between the adjacent vanes is limited to along the hinge during operation of the rotor assembly.
  • FIG. 1 is a schematic illustration of an exemplary gas turbine engine 10 coupled to an electric generator 16.
  • gas turbine system 10 includes a compressor 12, a turbine 14, and generator 16 arranged in a single monolithic rotor or shaft 18.
  • shaft 18 is segmented into a plurality of shaft segments, wherein each shaft segment is coupled to an adjacent shaft segment to form shaft 18.
  • Compressor 12 supplies compressed air to a combustor 20 wherein the air is mixed with fuel 22 supplied thereto.
  • engine 10 is a 6C gas turbine engine commercially available from General Electric Company, Greenville, South Carolina
  • compressor 12 In operation, air flows through compressor 12 and compressed air is supplied to combustor 20. Combustion gases 28 from combustor 20 propels turbines 14. Turbine 14 rotates shaft 18, compressor 12, and electric generator 16 about a longitudinal axis 30.
  • FIG 2 is an enlarged perspective view of an exemplary stator vane 40 that may be used with gas turbine engine 10 (shown in Figure 1 ). More specifically, in the exemplary embodiment, stator vane 40 is coupled within a compressor, such as compressor 12 (shown in Figure 1 ).
  • Figure 3 is a front view of a pair of stator vanes 40 and illustrates a relative circumferential orientation of adjacent stator vanes 40 when assembled within a stator assembly, used with a rotor assembly such as gas turbine engine 10 (shown in Figure 1 ).
  • Figure 4 is a cross-sectional view of the pair of stator vanes 40 and taken along line 4-4 (shown in Figure 3 ).
  • each stator vane 40 has been modified to include the features described herein.
  • each stator vane 40 When assembled within the stator assembly, each stator vane 40 is coupled to an engine casing (not shown) that extends circumferentially around a rotor shaft, such as shaft 18 (shown in Figure 1 ). As is known in the art, when fully assembled, each circumferential row of stator vanes 40 is located axially between adjacent rows of rotor blades (not shown). More specifically, stator vanes 40 are oriented to channel a fluid flow through the stator assembly in such a manner as to facilitate enhancing engine performance. In the exemplary embodiment, circumferentially adjacent stator vanes 40 are identical and each extends radially across a flow path defined within the rotor and stator assemblies. Moreover, each stator vane 40 includes an airfoil 60 that extends radially outward from, and in the exemplary embodiment, is formed integrally with, a base or platform 62.
  • Each airfoil 60 includes a first sidewall 70 and a second sidewall 72.
  • First sidewall 70 is convex and defines a suction side of airfoil 60
  • second sidewall 72 is concave and defines a pressure side of airfoil 60.
  • Sidewalls 70 and 72 are joined together at a leading edge 74 and at an axially-spaced trailing edge 76 of airfoil 60. More specifically, airfoil trailing edge 76 is spaced chord-wise and downstream from airfoil leading edge 74.
  • First and second sidewalls 70 and 72 respectively, extend longitudinally or radially outward in span from its root positioned adjacent base 62 to an airfoil tip 80.
  • Base 62 facilitates securing stator vanes 40 to the casing.
  • base 62 is known as a "square-faced" base and includes a pair of circumferentially-spaced sides 90 and 91 that are connected together by an upstream face 92 and a downstream face 94.
  • base 62 could include an arcuate surface.
  • sides 90 and 91 are identical and are substantially parallel to each other. In an alternative embodiment sides 90 and 91 are not parallel.
  • upstream face 92 and downstream face 94 are substantially parallel to each other.
  • a pair of integrally-formed hangers 100 and 102 extend from each respective face 92 and 94.
  • Hangers 100 and 102 engage the casing to facilitate securing stator vane 40 within the stator assembly.
  • each hanger 100 and 102 extends outwardly from each respective face 92 and 94 adjacent a radially outer surface 104 of base 62.
  • At least one of circumferential sides 90 and 91 includes a recessed or scalloped portion 110 that extends partially between radially outer surface 104 and a radially inner surface 112 of base 62.
  • Recessed portion 110 is sized and oriented to facilitate controlling an amount of contact between adjacent stator vanes 40 during rotor operation. More specifically, in the exemplary embodiment, recessed portion 110 extends from radially outer surface 104 towards radially inner surface 112 such that a hinge 116 is created adjacent radially inner surface 112.
  • a gap 118 is defined between adjacent stator vanes 40 and contact between the stator vanes is limited being only along hinge 116.
  • line contact between adjacent stators 40 is driven along the rotor assembly flow path.
  • line contact may be anywhere between hinge 116 and side 91.
  • upstream face 92 includes a recessed portion 120 that extends across face 92 between sides 90 and 91.
  • Recessed portion 120 is sized and oriented to facilitate controlling an amount of contact between stator vane 40, along face 92, and the engine casing. More specifically, in the exemplary embodiment, recessed portion 120 extends from hanger 100 to a hinge 117. As a result, line contact between each stator vane 40 and the engine casing is controlled. Alternatively, line contact may be anywhere along portion 120.
  • recessed portions 120 and 110 facilitates controlling stator-to-stator contact and stator-to-casing contact.
  • the enhanced control of the contact facilitates each stator base 62 being defined more accurately such that the stator vanes natural frequencies can be optimized more accurately to match predicted expermimental frequencies.
  • excitation responses induced within each stator vane 40 are facilitated to be reduced, thus resulting in fewer component failures and extending a useful life of the stator vanes.
  • each stator vane includes recessed portions that facilitate controlling circumferential and axial contact with each stator vane such that excitation responses induced within each stator vane during engine operation are facilitated to be reduced.
  • the redefined base geometry facilitates extending a useful life of the stator assembly and improving the operating efficiency of the gas turbine engine in a cost-effective and reliable manner.
  • stator vanes and stator assemblies are described above in detail.
  • the stator vanes are not limited to the specific embodiments described herein, but rather, components of each stator vane may be utilized independently and separately from other components described herein.
  • each stator vane recessed portion can also be defined in, or used in combination with, other stator vanes or with other stator or rotor assemblies, and is not limited to practice with only stator vane 40 as described herein. Rather, the present invention can be implemented and utilized in connection with many other vane, stator, and rotor configurations.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Claims (2)

  1. Rotor (12) comportant :
    un arbre (18) de rotor ; et
    une pluralité d'aubes fixes (40) de stator espacées sur le pourtour extérieur dudit arbre, chaque dite aube fixe de stator comprenant une base (62) et une pale profilée (60) solidaire de ladite base et s'étendant radialement vers l'extérieur depuis ladite base, chaque base comprenant une surface radialement extérieure (104) et une surface radialement intérieure (12) et des côtés (90, 91) espacés sur son pourtour et reliés l'un à l'autre par un côté amont (92) et un côté aval (94), une partie creuse (110) étant ménagée dans au moins un desdits deux côtés (90, 91) espacés sur le pourtour de ladite base et s'étendant depuis la surface radialement extérieure (104) vers la surface radialement intérieure (112) de façon qu'une articulation (116) soit créée au voisinage immédiat de la surface radialement intérieure (112), un intervalle (118) étant ménagé entre les aubes fixes (40) de stator adjacentes sur le pourtour de l'arbre et le contact entre les aubes fixes adjacentes (40) se limitant à la zone le long de l'articulation (116) pendant le fonctionnement du rotor.
  2. Rotor (12) selon la revendication 1, comportant en outre une paire de supports d'accrochage solidaires (100, 102) s'étendant depuis chacun des côtés amont et aval respectifs (90, 92) adjacents à la surface radialement extérieure (104) de la base, les supports d'accrochage s'engageant dans une enveloppe, une autre partie creuse (110) étant ménagée dans l'un desdits côté amont (92) et côté aval (94) et s'étendant depuis le support d'accrochage solidaire (100, 102) vers la surface radialement intérieure (112) de façon qu'une articulation (117) soit créée au voisinage immédiat de la surface radialement intérieure (112), le contact entre l'aube fixe (40) et l'enveloppe se limitant à la zone le long de l'articulation (117) pendant le fonctionnement du rotor.
EP06254529.8A 2005-08-30 2006-08-30 Dispositif pour contrôler le contact dans un assemblage statorique Expired - Fee Related EP1760268B1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11/214,500 US7597542B2 (en) 2005-08-30 2005-08-30 Methods and apparatus for controlling contact within stator assemblies

Publications (3)

Publication Number Publication Date
EP1760268A2 EP1760268A2 (fr) 2007-03-07
EP1760268A3 EP1760268A3 (fr) 2011-12-21
EP1760268B1 true EP1760268B1 (fr) 2013-05-08

Family

ID=37450994

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06254529.8A Expired - Fee Related EP1760268B1 (fr) 2005-08-30 2006-08-30 Dispositif pour contrôler le contact dans un assemblage statorique

Country Status (4)

Country Link
US (1) US7597542B2 (fr)
EP (1) EP1760268B1 (fr)
JP (1) JP2007064224A (fr)
CN (1) CN1924300B (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100166550A1 (en) * 2008-12-31 2010-07-01 Devangada Siddaraja M Methods, systems and/or apparatus relating to frequency-tuned turbine blades
US8523518B2 (en) * 2009-02-20 2013-09-03 General Electric Company Systems, methods, and apparatus for linking machine stators
US20140037439A1 (en) * 2012-08-02 2014-02-06 General Electric Company Turbomachine exhaust diffuser

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB938189A (en) * 1960-10-29 1963-10-02 Ruston & Hornsby Ltd Improvements in the construction of turbine and compressor blade elements
US4011718A (en) 1975-08-01 1977-03-15 United Technologies Corporation Gas turbine construction
US5127793A (en) 1990-05-31 1992-07-07 General Electric Company Turbine shroud clearance control assembly
US5513955A (en) 1994-12-14 1996-05-07 United Technologies Corporation Turbine engine rotor blade platform seal
US5639212A (en) 1996-03-29 1997-06-17 General Electric Company Cavity sealed compressor
DE29715180U1 (de) * 1997-08-23 1997-10-16 Mtu Muenchen Gmbh Leitschaufel für eine Gasturbine
FR2812906B1 (fr) 2000-08-10 2002-09-20 Snecma Moteurs Bague de retention axiale d'un flasque sur un disque
FR2831207B1 (fr) 2001-10-24 2004-06-04 Snecma Moteurs Plates-formes pour aubes d'un ensemble rotatif
US7094029B2 (en) 2003-05-06 2006-08-22 General Electric Company Methods and apparatus for controlling gas turbine engine rotor tip clearances
US7147440B2 (en) 2003-10-31 2006-12-12 General Electric Company Methods and apparatus for cooling gas turbine engine rotor assemblies
US6984112B2 (en) 2003-10-31 2006-01-10 General Electric Company Methods and apparatus for cooling gas turbine rotor blades
GB0328952D0 (en) * 2003-12-12 2004-01-14 Rolls Royce Plc Nozzle guide vanes
US7125222B2 (en) 2004-04-14 2006-10-24 General Electric Company Gas turbine engine variable vane assembly
US7121802B2 (en) * 2004-07-13 2006-10-17 General Electric Company Selectively thinned turbine blade
GB0423363D0 (en) 2004-10-21 2004-11-24 Rolls Royce Plc Rotor assembly retaining apparatus

Also Published As

Publication number Publication date
EP1760268A3 (fr) 2011-12-21
CN1924300A (zh) 2007-03-07
US20070048131A1 (en) 2007-03-01
EP1760268A2 (fr) 2007-03-07
US7597542B2 (en) 2009-10-06
CN1924300B (zh) 2010-09-01
JP2007064224A (ja) 2007-03-15

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